Correct, it is well known that they kept Swift a bizarre secret internally. It seems no one thought it would be a good idea to consult with the vast swathes of engineers that had been using the language this was intended to replace for the last 30 or so years, nor to consult with the maintainers of the frameworks this language was supposedly going to help write, etc. As you can imagine, this led to many problems beyond just not getting a large enough surface area of compiler performance use cases.
Of course, after it was released, when they seemed very willing to make backward-incompatible changes for 5 years, and in theory they then had plenty of people running into this, they apparently still decided to not prioritize it.
Honestly it follows the design of the rest of the language. An incomplete list:
1. They wrote it to replace C++ instead of Objective-C. This is obvious from hearing Lattner speak, he always compares it to C++. Which makes sense, he dealt with C++ every day, since he is a compiler writer. This language does not actually address the problems of Objective-C from a user-perspective. They designed it to address the problems of C++ from a user-perspective, and the problems of Objective-C from a compiler's perspective. The "Objective-C problems" they fixed were things that made Objective-C annoying to optimize, not annoying to write (except if you are a big hater of square brackets I suppose).
2. They designed the language in complete isolation, to the point that most people at Apple heard of its existence the same day as the rest of us. They gave Swift the iPad treatment. Instead of leaning on the largest collection of Objective-C experts and dogfooding this for things like ergonomics, they just announced one day publicly that this was Apple's new language. Then proceeded to make backwards-incompatible changes for 5 years.
3. They took the opposite approach of Objective-C, designing a language around "abstract principles" vs. practical app decisions. This meant that the second they actually started working on a UI framework for Swift (the theoretical point of an Objective-C successor), 5 years after Swift was announced, they immediately had to add huge language features (view builders), since the language was not actually designed for this use case.
4. They ignored the existing community's culture (dynamic dispatch, focus on frameworks vs. language features, etc.) and just said "we are a type obsessed community now". You could tell a year in that the conversation had shifted from how to make interesting animations to how to make JSON parsers type-check correctly. In the process they created a situation where they spent years working on silly things like renaming all the Foundation framework methods to be more "Swifty" instead of...
5. Actually addressing the clearly lacking parts of Objective-C with simple iterative improvements which could have dramatically simplified and improved AppKit and UIKit. 9 years ago I was wishing they'd just add async/await to ObjC so that we could get modern async versions of animation functions in AppKit and UIKit instead of the incredibly error-prone chained didFinish:completionHandler: versions of animation methods. Instead, this was delayed until 2021 while we futzed about with half a dozen other academic concerns. The vast majority of bugs I find in apps from a user perspective are from improper reasoning about async/await, not null dereferences. Instead the entire ecosystem was changed to prevent nil from existing and under the false promise of some sort of incredible performance enhancement, despite the fact that all the frameworks were still written in ObjC, so even if your entire app was written in Swift it wouldn't really make that much of a difference in your performance.
6. They were initially obsessed with "taking over the world" instead of being a great replacement for the actual language they were replacing. You can see this from the early marketing and interviews. They literally billed it as "everything from scripting to systems programming," which generally speaking should always be a red flag, but makes a lot of sense given that the authors did not have a lot of experience with anything other than systems programming and thus figured "everything else" was probably simple. This is not an assumption, he even mentions in his ATP interview that he believes that once they added string interpolation they'd probably convert the "script writers".
The list goes on and on. The reality is that this was a failure in management, not language design though. The restraint should have come from above, a clear mission statement of what the point of this huge time-sink of a transition was for. Instead there was some vague general notion that "our ecosystem is old", and then zero responsibility or care was taken under the understanding that you are more or less going to force people to switch. This isn't some open source group releasing a new language and it competing fairly in the market (like, say, Rust for example). No, this was the platform vendor declaring this is the future, which IMO raises the bar on the care that should be taken.
I suppose the ironic thing is that the vast majority of apps are just written in UnityScript or C++ or whatever, since most the AppStore is actually games and not utility apps written in the official platform language/frameworks, so perhaps at the end of the day ObjC vs. Swift doesn't even matter.
This is a great comment, you clearly know what you're talking about and I learned a lot.
I wanted to push back on this a bit:
> The "Objective-C problems" they fixed were things that made Objective-C annoying to optimize, not annoying to write (except if you are a big hater of square brackets I suppose).
From an outsider's perspective, this was the point of Swift: Objective C was and is hard to optimize. Optimal code means programs which do more and drain your battery less. That was Swift's pitch: the old Apple inherited Objective C from NExT, and built the Mac around it, back when a Mac was plugged into the wall and burning 500 watts to browse the Internet. The new Apple's priority was a language which wasn't such a hog, for computers that fit in your pocket.
Do you think it would have been possible to keep the good dynamic Smalltalk parts of Objective C, and also make a language which is more efficient? For that matter, do you think that Swift even succeeded in being that more efficient language?
Let me preface this by saying performance is complicated, and unfortunately far more... religious than you'd expect. A good example of this is the Objective-C community’s old insistence that good performance was incompatible with garbage collection, despite decades of proof otherwise. This post [1] about Swift getting walloped by node.js is fascinating in seeing how a community responds with results that challenge their expectations (“what do you expect, the JS BigInt is optimized and ours isn’t”, “It’s slower, but uses less RAM!”, etc.). As it turns out, questions like GC vs. reference counting, often end up being much more nuanced (and unsatisfactory) than which is simply "faster". You end up with far more unsatisfying conclusions like one is more deterministic but often slower (and as it turns out most UIKit apps aren’t realtime systems).
All this to say, it is hard to answer this question in one comment, but to try to sum up my position on this, I believe the performance benefits of Swift were and remain overblown. It’s a micro benchmark based approach, which as we’ll see in a second is particularly misguided for Swift's theoretically intended use case as an app language. I think increasingly people agree with this as they haven't really found Swift to deliver on some amazing performance that wouldn’t have been possible in Objective-C. This is for a number of reasons:
1. As mentioned above, the most important flaw with a performance based Swift argument is that the vast majority of the stack is still written in Objective-C/C/etc.. So even if Swift was dramatically better, it’s only usually affecting your app’s code. Oftentimes the vast majority of the time is spent in framework code. Think of it this way: pretend that all of iOS and UIKit were written in JavaScript, but then in order to “improve performance” you write your app code in C. Would it be faster? I guess, but you can imagine why it may not actually end up having that much of an effect. This was ironically the bizarre position we found ourselves in with Swift: your app code was in a super strict typed language, but the underlying frameworks were written in a loosey-goosey dynamic language. This is exact opposite of how you'd want to design a stack. Just look at games, where performance is often the absolute top priority: the actual game engine is usually written in something like C++, but then the game logic is often written in a scripting language like Lua. Swift iOS apps are the reverse of this. Now, I'm sure someone will argue that the real goal is for the entire stack to eventually be in Swift, at which point this won't be an issue anymore, but now we're talking about a 20-year plan, where it seems weird to prioritize my Calculator app's code as the critical first step.
2. As it turns out, Objective-C was already really fast! Especially since, due to its ability to trivially interface with C and C++, a lot of existing apps in the wild had already probably topped out on performance. This wasn't like you were taking an install base of python apps and getting them all to move over to C. This was an already low-level language, where many of the developers were already comfortable with the "performance kings" of the C-family of languages. Languages, which, for the record, have decades of really really good tooling specifically to make things performant, and decades of engineering experience by their users to make things performant. And so, in practice, for existing apps, this often felt more like a lateral move. I actually remember feeling confused when after the announcement of Swift people started talking about Objective-C as if it was some slow language or something. Like, literally the year before, Objective-C was considered the low-level performance beast compared to, say, Android's use of Java. Objective-C just wasn't that that slow of a comparison point to improve that much on. The two languages even share the same memory management model (something that ends up having a big affect on its performance characteristics). Dynamic dispatch (objc_msgSend) just does not really end up really dominating your performance graph when you profile your app.
3. But perhaps most importantly, I think there is a mirror misguided focus on language over frameworks as with the developer ergonomics issues I pointed out above. If you look at where the actual performance gains have come from in apps, I’d argue that it’s overwhelmingly been from conceptual framework improvements, not tiny language wins. A great example of this is CoreAnimation. Making hardware accelerated graphics accessible through a nice declarative API, such that we can move as much animation off the CPU and onto the GPU as possible, is one of the key reasons everything feels so great on iOS. I promise no language change will make anywhere near as big of a dent as Apple's investment in CoreAnimation did. I’d argue that if we had invested development time in, e.g., async/await in Objective-C, rather than basically delaying that work for a decade in Swift, we’d very possibly be in a much more performant world today.
Anyways, these are just a few of thoughts on the performance-side of things. Unfortunately, as time moves on, now a decade into this transition, while I find more people agreeing with me than, say, when Swift was first announced, it also becomes more academic since it's not like Apple is going to go back and try to make Objective-C 3 or something now. That being said, I do think it is still useful to look back and analyze these decisions, to avoid making similar mistakes in the future. I think the Python 2 to 3 transition provided an important lesson to other languages, I hope someday we look at the Swift introduction as a similar cautionary tale of programming language design and community/ecosystem stewardship and management.
To add to the GC discussion, something that many that weren't around during the GC project failure for Objective-C, is that ARC was pivot from a failed project, but in good Apple fashion that had to sell the history on their own way.
The GC for Objective-C failed, because of the underlying C semantics, it would never be better than a typical conservative GC, and there were routinely application crashes when mixing code compiled with GC and non-GC options.
Thus they picked up the next best strategy, which was to automate the Cocoa's retain/release message pairs, and sell that as being much better than GC, because performance and such, not because the GC approach failed.
Naturally, as proven by the complex interop layer in .NET with COM, given Objective-C evolution, it would also be much better for Swift to adopt the same approach, than creating a complex layer similar to CCW/RCW.
Now everyone that wasn't around for this, kind of believes and resells the whole "ARC because performance!" story.
Do you happen to have any source/book on why you can't use anything but a conservative gc on C-like languages? I would really like to know why that's the case.
Basically C semantics are to blame, due to the way C was designed, and the liberties it allows its users, it is like programming in Assembly from a tracing GC point of view.
Meaning that without any kind of metadata, the GC has to assume that any kind of value on the stack or global memory segments is a possible pointer, but it cannot be sure about it, it might be just a numeric value that looks like a valid pointer to GC allocated data.
So any algorithm that needs to be certain about the exact data types, before moving the wrong data, is already off the table in regards to C.
Great posts. Objective-C is still my programming language of choice.
> Now, I'm sure someone will argue that the real goal is for the entire stack to eventually be in Swift, at which point this won't be an issue anymore, but now we're talking about a 20-year plan, where it seems weird to prioritize my Calculator app's code as the critical first step.
It seems like it is the goal for at least some people at Apple. But so many
Swift frameworks rely on Objective-C frameworks (SwiftUI wraps lots of UIKit. SwiftData is built on top of CoreData, etc.)
In twenty years Swift will be roughly the same age Objective-C was when Swift was introduced (give or take). By then the Swifties will be getting old and gray. I think it’s reasonable to bet that some young blokes will be pushing a new programming language/UI framework by then. I’m not sure Apple can replace the entire Objective-C stack even if they wanted to. Maybe if they spent the next five years not working on any new features and did nothing but port all the frameworks to pure Swift (we know Apple will never do that).
Unless a new hardware platform takes off and supersedes iOS/macOS and starts Swift only I just don’t think Apple can rid themselves of Objective-C (I personally think that they shouldn’t even want to get rid of Objective-C). But watchOS doesn’t have many developers and visionOS wants all existing iOS and macOS apps to work because they want a large ecosystem.
I sometimes wonder if Objective-C will outlive Swift. Sure it’s the underdog but I always root for the underdog. I hope someone will make an Objective-C 3.0 even if it isn’t Apple.
As someone interested in Apple app dev, would you recommend still starting with ObjC? I notice the dev behind the Swiftcord app (open source Discord client in Swift) has noted at length how much you still need to call into UIKit to get things done as there were a lot of blind alleys in SwiftUI.
great context. the whole narrative you present kind of begs the question of whether swift could actually be a good systems language.
as a SwiftUI app dev user I feel like this (and the OP's post) lines up with my experience but I've never tried it for e.g. writing an API server or CLI tool.
I think this is actually the security researcher's fault. If you read the small print, this kernel bug doesn't meet the Bug Bounty Qualification Criteria of being on an OS that Apple actually gives a shit about.
They did Apple a solid, but not in accordance with the precise terms as laid out by Apple, so it's perfectly justified for Apple to take the researcher's work for nothing?
There is also a secondary effect where more complex systems generate a bunch of surrounding materials: tutorials, videos, etc. It also creates job security for the people who learn it, as they have a necessary skill and responsibility in the company, as opposed to something that "just works" which doesn't require that.
Of course. If you were running an evil open-source company, you would favor "solutions" that generates demand for the services you sell (training, tech support contracts,...) while maintaining the belief that all this is necessary in "modern" IT.
I think it's Rich Hickey who links in his one of his talks complexity with entanglement through etymology. This entanglement is sometimes also there to bind the customer. Although more often the "never attribute to malice..." rule is at work, as it's just easier, cheaper, etc... to let the complexity grow.
I think this is a pretty clear misrepresentation. The entire point of those forum posts is that software engineers are angry at managers promising timelines that aren't connected to reality: they want the unpredictability of the task to be transparent. That is actually entirely consistent, and arguably the exact same frustration, that they have with Musk -- a manager-type promising outrageous deadlines, repeatedly, with apparently zero ability to learn from past misses. The anger is with continuing to promise these outrageous deadlines, and furthermore the frustration of being called out if you are skeptical of them, not with the fact that he misses them. It's a one-to-one, 100%, absolutely identical complaint.
"We couldn't figure out how to make a bunch of people buy this ugly thing unless they were already neck-deep in the ecosystem. For three years we tried to make it legitimately useful in its own right! Or at least somewhat attractive. You know, so that if you wear it in a photo it doesn't immediately date the photo. Then when you look at a nice photo where everyone is dressed up there isn't this ugly thing on your wrist that screams "2015!" or whatever. But yeah, this is a tough nut to crack. I'd go so far as to say it's an AirPower-level problem in terms of difficulty."
Is there a good explanation of u substitution (or any other integral stuff that makes use of the denominator) using non-Liebnitz notation? Is it just that ∂1 is actually ∂/∂1, and thus you can begin using ∂1 the way you would have used ∂x?
If you mean u-substitution in definite integrals, that is something called the change of variables theorem. I think you mean indefinite integrals or antiderivatives, and I think you're asking for an explanation with using the "du/dx" sort of notation. Here's a quick explanation which may be more than you wanted to know. :-)
You have ∫ f(g(x)) g'(x) dx. [So it might be something like ∫ [cos(x^2)] (2 x) dx, where f(x) = cos x and g(x) = x^2.] You do the u-substitution u = g(x), so u'(x) = g'(x):
∫ f(g(x)) g'(x) dx = ∫ f(u) u'(x) dx
You want to say that the second integral is ∫ f(u) du -- essentially (to go back to "fractional" derivative notation), you want to do (du/dx) dx = du to get rid of the x's. Why is this justified?
Let F(u) = ∫ f(u) du: F is the antiderivative of f. By definition of the antiderivative, F'(u) = f(u). So by the Chain Rule,
d/dx F(u) = F'(u) u'(x) = f(u) u'(x).
But since F(u) = ∫ f(u) du differentiates to f(u) u'(x), by definition F(u) is the antiderivative of f(u) u'(x). But the antiderivative of f(u) u'(x) is ∫ f(u) u'(x) dx. So putting all this stuff together,
This is worse than my 365 month calendar since it still has that ugly 5-day “year end”. In my calendar, every month is exactly one day long, no exceptions. Leap years simply add an extra month.
I think the 5 day "year end" is actually fine. So many people take lots of holidays around the end of the year so that period is kinda messed up anyways. It seems that it would be nice to just give everyone 5 days off and sort of unify it.
Since unfortunately 365 isn't a round number it seems like the best compromise. The other top approach would be counting days.
Perhaps the AGI correctly reasoned that the best (or easiest?) initial strike on humanity was to distract them with a never-ending story about OpenAI leadership that goes back and forth every day. Who needs nuclear codes when simply turning the lights on and off sends everyone into a frenzy [1]. It certainly at the very least seems to be a fairly effective attack against HN servers.
How is it different than someone making a funny video where they impersonate David Attenborough? Those aren’t generally considered disrespectful, right?
Like, I get the potential scale is different. But this is some joke video, not someone trying to actually replace David Attenborough or something.
I agree and the difference is commercial rights and intent. Parody, jokes, etc are fine. Using this to replace him on a documentary, not okay. Fair use already covers this all they have to do is extend copyright protections to peoples likeness and voices
> Using this to replace him on a documentary, not okay.
I think it's legal if you're the copyright holder, e.g. Disney putting dead actors in their movies did not need anybody's permission, nor does any derivative work such as videogames as they own the image right to the characters they play.
It would be interesting if they did a Planet Earth IV with Attenbrough's voice without his consent as David plays himself really...Not a fictional character.
Correct, it is well known that they kept Swift a bizarre secret internally. It seems no one thought it would be a good idea to consult with the vast swathes of engineers that had been using the language this was intended to replace for the last 30 or so years, nor to consult with the maintainers of the frameworks this language was supposedly going to help write, etc. As you can imagine, this led to many problems beyond just not getting a large enough surface area of compiler performance use cases.
Of course, after it was released, when they seemed very willing to make backward-incompatible changes for 5 years, and in theory they then had plenty of people running into this, they apparently still decided to not prioritize it.